About ElecCalc
ElecCalc is a free suite of 25 electrical calculators for Australian and New Zealand electricians, apprentices and designers, with long-form guides that explain the method behind each one. There is no login, no paywall and no watermark on the PDF reports. It is built by a working electrician in Adelaide and run by SEY Solutions.
Why it exists
Sparkies need quick, reliable calculations on a phone on site, and apprentices need to see how an answer was reached, not just the number. ElecCalc does both: every calculator shows its working with your own figures substituted in, and cites the clause or table each step comes from, so you can check it against your copy of the standard.
How the calculators are checked
- Checked against the standards, not memory. In August 2026 every guide, every calculator page and the practice quiz were audited clause by clause against AS/NZS 3000:2018 and AS/NZS 3008.1.1. That audit found and corrected 76 errors, including a single-phase voltage drop formula published without its factor of two and an earth conductor table that undersized three conductor sizes.
- Tested against published worked examples. Where a standard publishes worked examples, the calculator reproduces them as automated tests. The arc flash calculator, for example, matches every intermediate value in the IEEE 1584:2018 Annex D examples and agrees with the official IEEE spreadsheet calculator across more than 100,000 cases.
- Over 2,200 automated tests. Every calculation engine is covered by tests that run before any change goes live, including regression locks on tables that have been transcribed from the standard.
- Approximate values are labelled. Where a lookup value is indicative rather than transcribed from the current edition of a standard, the working says so next to the step that uses it.
- Inputs outside a model's range are refused. Where a method has a published valid range, such as the IEEE 1584 arc flash model, the calculator says so instead of returning a number it cannot stand behind.
Corrections
Reader reports are the most valuable feedback ElecCalc gets, and several have led to real fixes. A reader pointed out that fixed appliances need RCD protection under AS/NZS 3000 Clause 2.6.3.2.2, which the site had wrong in five places. A principal electrical engineer reported that the arc flash calculator was overstating incident energy; it was taken offline the same day and rebuilt on the full IEEE 1584:2018 model.
Every report is checked against the standard. If the site is wrong, it is fixed and the fix is tested so it cannot quietly come back. If you think a result or a clause reference is wrong, send it in.
How it works
Every calculator runs entirely in your browser, so the figures you enter are not sent to a server. Results update as you type. You can export a PDF report or save a result to your calculation history, which is stored on your device only. ElecCalc also installs to your home screen as an app and works offline once installed.
Who is behind it
ElecCalc is built and maintained by SEY Solutions, an Adelaide software business (ABN 13 531 353 123) that builds tools for the Australian electrical trade, including the SparkyToolkit app for iOS. ElecCalc is free and funded by its users; see how to support it.
Using the results
ElecCalc is a design aid. Check results against the current edition of the relevant standard and the manufacturer's data, and have the design signed off by the person responsible for the installation. The full terms are in the terms of use.
Get in touch
Questions, corrections or feedback: jack@seysolutions.com.au